1. Field of the Invention
The present invention relates to grout-delivery systems for supplying flowable grout from a storage hopper through a flexible hose to a hand-held nozzle structure for application to a work surface, which may comprise areas bordering bricks, floor tiles, metal doors or metal windows, etc.
2. Prior Art
Systems for delivering grout or wet plaster to work areas are already known. U.S. Pat. No. 3,140,801 to Delligatti discloses a plaster delivery system including a cylindrical supply hopper having vertical axis agitator means driven by an overhead motor. A horizontal gate valve controls downflow of wet plaster from the hopper into the pumping chamber of a piston-operated pump. The pumping piston has a ball check valve to allow the plaster to flow through the piston in the pumping direction.
U.S. Pat. No. 3,227,426 to Williams discloses a grout-delivery system wherein a single electric motor drives a grout-delivery pump and a vertical axis agitator in a grout supply hopper. The power connection includes a power take-off unit having a vertical shaft connected to the agitator, and a horizontal shaft connected to the pump. A clutch is disposed between the horizontal shaft and the pump, whereby the agitator can continue operating while the pump is stopped. The agitation action prevents grout in the hopper from prematurely hardening.
U.S. Pat. No. 3,768,939 to Gramling discloses a mortar delivery system wherein a known Moyno pump is located below a mortar-supply hopper for delivering mortar through a flexible hose and into a specially constructed nozzle which has a projecting guide means and mortar-striking protuberance to facilitate the flow of mortar into the spaces between rows of bricks. The pump motor is turned on or off by means of a pushbutton switch on the nozzle.
U.S. Pat. No. 5,122,038 to Malkoski discloses a grout pumping system that includes a vertical axis agitator means disposed in an upright cylindrical hopper. The pumping unit includes a horizontal axis auger located below the hopper, said auger having an array of rod-like shear blades which recirculate some of the grout back into the hopper, thus to more thoroughly mix the grout ingredients. The pumping unit is formed in separable sections that can be taken apart for cleaning purposes.
There is no provision in the above-noted patented systems for controlling or varying the flow rate of the grout (or plaster) through the nozzle structure. The operator of the nozzle cannot control the amount of mortar or grout discharged onto the work surface. There thus can be spills or smearing of the grout onto unwanted surfaces. At the other extreme, the grout flow rate may be so slow as to interfere with worker productivity.